Nutrient Dynamics in the Ria Formosa Lagoon:

Implications for Surveillance Monitoring of Chemical Quality

Elements in Accordance with the Water

Framework Directive

Alice Newton1 and John D. Icely2

IMAR and SagremariscoIMAR and Sagremarisco

ELOISE Conference in Portoroz, Slovenia, 15-18 November 2004

OAERRE, part of the ELOISE cluster EU contract nº EVK3-CT1999-0002

Making our science usefulMaking our science useful

• HowHow can we use the scientific results can we use the scientific results from ELOISE projects?from ELOISE projects?

• ELOISE projects ELOISE projects cancan supply valuable supply valuable information for managersinformation for managers

• An example: data for the An example: data for the implementation of the Water implementation of the Water Framework DirectiveFramework Directive

Added value and financial Added value and financial benefitsbenefits

• As As Daniel ConleyDaniel Conley said on Monday, said on Monday, scientists need data, data, datascientists need data, data, data

• Managers need to implement Managers need to implement expensive monitoring plans €€€€€€€expensive monitoring plans €€€€€€€€!€!

• Our results can inform as to Our results can inform as to wherewhere and and whenwhen to monitor to get the to monitor to get the maximum information maximum information

Science and WFD Jargon…Science and WFD Jargon…

• The Ria Formosa is a coastal lagoon in southern

Portugal.

• The implementation of the Water Framework

Directive (WFD) includes the design of monitoring

plans for water bodies.

• Under the WFD typology, the lagoon has been classified

as a sheltered coastal water in the North East Atlantic

(NEA) Geographical Intercalibration Group (GIG).

B B : Inlet exchanging with the oceanP P: Shallow upstream channelR R: Inner channel adjacent to the UWWT outlet

Location of the Ria Formosa, Portugal and study area

Sampling strategy • The nutrient dynamics in the western part of the

lagoon were studied in the ELOISE-OAERRE project. • The sampling strategy was designed to take into

consideration the time of day, the state of the tide, the amplitude of the tide (Spring- Neap) and the time of the year.

• Tidal conditionsHigh water + Mid-ebb +Low water + Mid-flood

• Tidal amplitudeSpring tides + Neap tides

• SeasonsSpring equinox +Summer solstice+Autumn equinox + Winter solstice

Methods and the WFDMethods and the WFD

• The Chemical Water Quality Elements listed under ANNEX V of the WFD were chosen for the study.

• These include:Oxygenation Salinity Nutrients

• Phytoplankton was the main Biological Quality Element used in the study.

Metrics for PhytoplanktonMetrics for Phytoplankton •Chlorophyll a and other pigments•Primary Production

(14C and Oxygen methods)

•eta “” proportion of the microplankton community that is heterotrophic

•psi “ ” proportion of the autotrophic phytoplankton community that is not dependent on silicon(Poster by Loureiro et al : Nutrient and microplankton dynamics in the Ria Formosa lagoon)

LOTS of LOTS of scientific scientific results !results !

NUTRIENT CONCS, TEMP. & SALINITY - NEAP TIDE

0

0.1

0.2

0.3

0.4

0.5

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0.8

1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233343536373839404142434445464748495051

TIME - 1/2 HOUR INTERVALS

CO

NC

. u

mo

les/

L

0

5

10

15

20

25

30

35

40

45

TE

MP

. S

AL

INIT

Y NITRATE:N

NITRITE:N

PHOS:N

Salinity

Temperature

HIGH WATER

LOW WATER

HIGH WATER

LOW WATER

HIGH WATER

NUTRIENT CONCS, TEMP & SALINITY - SPRING TIDE

0

0.5

1

1.5

2

2.5

3

1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233343536373839404142434445464748495051

TIME - 1/2 HOUR INTERVALS

NIT

RA

TE

, N

ITR

ITE

, P

HO

SP

HA

TE

0

5

10

15

20

25

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35

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. &

SA

LIN

ITY

NITRATE:S

NITRITE:S

PHOS:S

Salinity

Temperature

HIGH WATER

LOW WATER

HIGH WATER

LOW WATER

Data, Data, data, data, data !data !

Interpretation of results:

• Water quality of the western lagoon is not homogenous.

• The area around the Ponte is of good water quality.

• The area near Ramalhete is of moderate water quality.

ASSETS screening model (Nobre et al)

DiscussionDiscussion

•The tidal exchange of water with the Atlantic at the Barra inlet is sufficient to ensure good water quality throughout most of this shallow lagoon.

•However, this lagoon is surrounded by agricultural and urbanized land and some of the inner parts of the Ria Formosa are susceptible to eutrophication.

Results and the WFDResults and the WFD On the basis of the

results from OAERRE project, the Ponte and the Ramalhete sites have been indicated as appropriate for the WFD intercalibration exercise in 2005.

Conclusion…scientific results•Ana Nobre’s presentation on Monday showed us that sampling frequency is important

•It is also important to understand the temporal variations in nutrient dynamics imposed by •Daily tidal cycles,•Spring-Neap tidal cycles, •Solstice and Equinox cycles and•Seasonal cycles.

Conclusion for WFD Conclusion for WFD implementationimplementation

• The results can be utilized in the design of the monitoring plans as part of the Common Implementation Strategy (CIS) of the WFD.

• Under the WFD, there are three distinct types of monitoring: surveillance, operational and investigative.

• To optimize the timing and sampling frequency of surveillance monitoring.

References…the science • Newton,A. & Mudge, S.M. 2003. Temperature and salinity regimes in a shallow , mesotidal lagoon,

the Ria Formosa. Portugal. Estuarine, Coastal and Shelf Science 57, 73-85.

• Newton, A., Icely, J.D, M.Falcao , A.Nobre, J.P.Nunes, J.G. Ferreira, C.Vale 2003 Evaluation of Eutrophication in the Ria Formosa coastal lagoon, Portugal. Continental Shelf Research 23, 1945–1961

• Tett , P., Gilpin,L., Svendsen, H., Erlandsson,C. , Larsson,U. , Kratzer,S. , Fouilland, E., Janzen,C., Jae-Young Lee , Grenz, C. , Newton, A., Ferreira,J.G. Fernandes, T., Scory, S. 2003Eutrophication and some European waters of restricted exchange. Continental Shelf Research 23, 1635–1671

• Newton,A. & Mudge, S.M (In press) Lagoon-sea exchanges, nutrient dynamics and water quality management of the Ria Formosa (Portugal) Estuarine, Coastal and Shelf Science

• Newton, A. & Icely, J.D. (In press) Oceanographic Applications to Eutrophication in Tidal, Coastal Lagoons, the Ria Formosa, Portugal. Journal of Coastal Research.

• Edwards, V., Icely, J.D., Webster, R., Newton, A. (In press)A comparison of the yield of chlorophyll from nitrogen between the lagoonal waters of the Ria Formosa and the oceanic waters off Sagres on the southern coast of Portugal. Estuarine, Coastal and Shelf Science

• Icely, J. D., Mendes, P., Galvão, H., Newton, A., Pereira, G. (In press) Pelagic primary and bacterial production of the Ria Formosa: a mesotidal lagoon in southern Europe. Hydrobiologia

• Loureiro,S., Newton, A., Icely, J.D. (In press) Effects of Nutrients Entering the Ria Formosa Coastal Lagoon (Southern Portugal): Enrichment Experiments and Primary Production. Hydrobiologia

• Loureiro S., Newton, A., Icely, J.D. (In press) Nutrient availability and microplankton assemblage in the Ria Formosa coastal lagoon (S. Portugal) Estuarine, Coastal and Shelf Science

• Nobre,A. Ferreira,J.G., Newton,A. , Simas,T. Icely, J.D., Neves, R. (In submission.) Managing eutrophication: Integration of field data, ecosystem-scale simulations and screening models. Journal of Marine Systems

Thank you… Questions? Thank you… Questions?

OAERRE, part of the ELOISE cluster EU contract nº EVK3-CT1999-0002